This invention relates to a method for presetting a machine, such as a printing press, which produces multiple copies of a product which are judged as to acceptability at least in part by subjective operator evaluation.
This invention has application to any machine or process wherein an objective standard may be used initially in presetting the machine, and wherein the machine output can thereafter be varied or adjusted in accordance with a subjective determination by its operator.
A typical example is in the setting of each of the ink fountains on a printing press. Each fountain is provided with a plurality of keys all of which are adjusted prior to printing to meter the amount of ink flowing onto the printing plate. In manually operated presses, the pressman will first scan visually the printing plate and estimate the amount of ink needed within each of the sections controlled by the keys of the ink fountain. There are other systems, wherein an optical scanner is used to scan a printing plate to determine the amount of ink needed within certain narrow sections of the printing plate, and that information is then processed to set automatically the corresponding keys of each fountain.
Many modern day presses are provided with electromechanical means for setting the keys from a remote location, and also transducers for indicating each key position at a remote location, for example, on a television screen. Also, means may be provided to record the information from the optical scanner regarding the percentage of coverage on the printing plate for each key position. Key position and other press information deemed by the pressman to represent the best printing quality is recorded so that if the printing run were interrupted, for whatever reason, that information could then be recalled and used to preset the machine when printing is resumed using those same plates.
Previously, the keys of the fountain were preset either according to the judgment of the pressman or by automatic means as described above. Once these initial adjustments were made, the press was then started, and further adjustments made to the fountains, and other systems, such as to compensate for registration of various colors, water fountains, etc., to improve the quality of the output until it achieved acceptable quality, known as "save" quality. As the press continued to run, still further fine adjustments were made by the pressman until, usually after several hours of running, a quality of printing of high grade results, known as "OK" quality. It is the "OK" quality settings that are recorded for later use should the printing operation be interrupted, for example by a priority printing job, during the middle of a run.
It is the purpose of this invention to utilize the pressman's previous subjective judgments as a means for modifying the objective information obtained from the optical scanning of a print plate to generate key setting information which will result in acceptable quality printing as early in the press run as possible.